An experiment has 10 equally likely outcomes. Let A and B two non – empty events of the experiment. If a consists of 4 outcomes, the number of outcomes that B must have so that A and B are independent, is
5 or 10
Let nB and nA ∩ B denote the number outcomes favorable to B and A ∩ Brespectively.
As A and B are independent.
P(A ∩ B) = P(A) P(B)
⇒ nB = 5 or 10. [âˆµ 1 ≤ nB ≤ 10.]
A group of 2n boys and 2n girls is randomly divided into two equal groups. The probability that each group contains the same number of boys and girls is
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